If you could ask Mary Berry one baking related question, what would it be?

The one and only Mary Berry is launching an app called Mary Berry Bakes in a few short weeks.

The app will have 70 recipes, from quick traybakes and biscuits to savoury nibbles and sponge cake.

To celebrate, Mary has asked us for some baking questions, which she'll answer in a short video. Since we know how much you love her - as this webchat with her made clear, we thought we'd hand over the question-asking to you.

Have you had any baking disasters that Mary could help you with? Do you want to know how to make the perfect sponge?

Post your questions below and we will select a few to be put to Mary and we will share the video with you when it's been made.

Which is better for baking, an electric oven or a gas oven? I'm perfectly comfortable using the different heat zones of a fan-less gas oven, that's not an issue for me at all. But, does the fact that water is a by-product of gas combustion make a gas oven a more humid environment than an electric oven, and does that affect baking?

How do you get your Victoria sponges to rise level, mine always have a peak in the middle and also I have an aga but always play safe by baking in the electric oven, is baking in an aga easy?? Or should I stick to conventional??

Do you have any foolproof recipes that are egg and dairy (or at least butter, I can improvise with non-dairy milks, but butter alternatives aren't great)? Baking for a child that's allergic to both, but still wanting the family to enjoy the results can sometimes be frustrating.

Why do some recipes call for plain flour with baking powder and others for self raising? Can you substitute one for the other in these recipes? I even have a recipe that uses plain, raising agents and then SR flour as well...is this unnecessary faff?

Ooh yes, intrigued by the value flour question and the butter one. Is the butter about consistency? I also bake with butter, but get it really soft first - is recommending margarine just about "foolproofing" it?

Squarecircle this link explains the difference. Bicarbonate of soda requires a source of acid to react with to make the carbon dioxide which makes your cake rise. It is generally used in recipes which have an acidic ingredient (e.g. buttermilk, lemon juice). Baking powder is a mixture of bicarb and acid, so you don't need to add an acidic ingredient. So they aren't interchangeable.